 
(* ::Section:: *)
(* CartesianIndex *)
(* ::Text:: *)
(*CartesianIndex is the head of Cartesian indices. The internal representation of a three-dimensional i is CartesianIndex[i]. For other than three dimensions: CartesianIndex[i, Dimension]. CartesianIndex[i, 3] simplifies to CartesianIndex[i]. The first argument cannot be an integer..*)


(* ::Subsection:: *)
(* See also *)
(* ::Text:: *)
(*LorentzIndex, ExplicitLorentzIndex.*)



(* ::Subsection:: *)
(* Examples *)
(* ::Text:: *)
(*This denotes a 3-dimensional Cartesian index.*)


CartesianIndex[i]


(* ::Text:: *)
(*An optional second argument can be given for a dimension different from 3.*)


CartesianIndex[i,D-1]

CartesianIndex[i,D-4]
